This invention relates to identifying the location of a sequence of data bits on a storage medium.
Data stored on a mass storage device such as a magnetic disk is typically organized in sectors. In each sector the sequence of data bits is immediately preceded by a predetermined synchronization sequence (the same synchronization sequence is used for each sector). Thus the synchronization sequence effectively points to the place where the data bit sequence begins. Each sector also includes a header address; a second synchronization sequence points to the beginning of the header address.
One known synchronization sequence--a long string of zero-valued bits followed by a final one-valued bit--works well if the bit error rate for the storage medium is low (for example, on the order of 10.sup.-12).
More complicated synchronization sequences of binary bits can cope with larger error rates, e.g., on the order of 10.sup.-10 or 10.sup.-9.